Catastrophe Current Year Claims and Claims Adjustment Expense

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 55
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480046/944-40-55-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480081/944-40-50-3

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Unpaid Losses And Loss Adjustment Expenses (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Catastrophe Current Year Claims and Claims Adjustment Expense	$ (5,187)	$ 0	$ 60,877	$ 0
Favorable (adverse) development on prior years' loss reserves			228,839	221,298
California Wildfires (2025)
Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Catastrophe Current Year Claims and Claims Adjustment Expense			(60,900)
Markel Insurance
Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Catastrophe Current Year Claims and Claims Adjustment Expense	$ (5,187)	$ 0	60,877	0
Markel Insurance \| Marine & Energy, Propety, Professional Liability, and Workers' Compensation product lines
Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Favorable (adverse) development on prior years' loss reserves			177,900
Markel Insurance \| Run-off risk-managed directors and officers product lines
Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Favorable (adverse) development on prior years' loss reserves			$ (127,900)
Markel Insurance \| International Professional Liability, International Marine & Energy, and Property product lines [Member]
Liability for Unpaid Claims and Claims Adjustment Expense [Line Items]
Favorable (adverse) development on prior years' loss reserves				$ 165,700